Winter Storm — Southern Grafton, New Hampshire

2024-01-07 · Southern Grafton, New Hampshire

Event narrative

Light to moderate snow began late in the evening on the 6th. Heavy snow began early in the morning on the 7th as a mesoscale band forced by strong warm air advection lifted in the Upper Valley and settled overhead into the afternoon. Snowfall rates in excess of 1 to 2 inches per hours were observed throughout the event. Snow ended quickly once surface winds veered to northwesterly. Snowfall totals ranged from 8 to 14 inches.

Wider weather episode

Early on the 6th low pressure began organize along the Gulf Coast as high pressure settled into southern Quebec. This high pressure brought some fresh cold air ahead of the developing East Coast storm. Early on the 7th the storm center had moved to a position near Chesapeake Bay and was beginning to occlude. By this time light snow was already breaking out across New Hampshire as warm, moist air was forced over the cold dome. Slow deepening continued as the nor'easter approached Nantucket, with the strongest forcing sent a mesoscale band of heavy snow north into the Lakes Region where it settled through the afternoon. Snowfall rates in excess of 1 to 2 inches per hour were frequently observed underneath this band. The storm began to exit east northeast and snow generally ended from west to east into the early evening hours on the 7th.

Source: NOAA Storm Events Database, event_id 1147397. Narrative written by the NWS forecast office that issued the report.